SCO crosses Microsoft's Maginot line

Claims Redmond was looking the other way...

Common Topics

If you can't get them round the front - try round the back. Following on from Novell's reverse engineered NDS-for-NT, the Santa Cruz Operation has become the latest intrepid to pop behind Microsoft's Maginot line.

Intriguingly, on this occasion it seems the work has been done with some degree of connivance from Redmond - but more on that in a moment. SCO has reverse-engineered Microsoft's RDP protocol used by Windows NT Terminal Server (and from February on, all Windows 2000 Server editions) to display multi-user NT apps on thin clients. SCO had originally floated the idea of reverse engineering RDP as a contest for open source hackers, but its British Cambridge team - who came on board when SCO acquired IXI and VisionWare a few years back - fancied they could do the job themselves, and they did.

Their handiwork will ship in the next version of its Tarantella 'application broker' thin client middleware in the new year. But this is more than an idle hack, and anyone sensibly wanting to take the work of running Windows applications away from the PCs Bill intended them to run on - a move which has proved a big cost-saving win in recent years - should take note.

Under the five-year joint development agreement between Citrix and Microsoft, Redmond agreed to support RDP only for Windows clients - Windows PCs, or terminals running embedded CE. Citrix was left to promote its own ICA protocol to non-Windows devices - and to support ICA meant buying the expensive MetaFrame server add-on. So for CIOs with Mac, Unix or OS/2 desktops then, or those wanting to buy cheaper non-CE devices, ICA has been the only game in town and MetaFrame a compulsory purchase. Which is where SCO steps in.

Tarantella sits on its own Unix box or server farm - not necessarily SCO's Unix - and delivers streams from green screen 3270 and Wyse terminals and X applications to a Java-enabled browser. This has a few neat advantages. Tarantella uses its own optimising protocol which allows X.11 to be piped over a dial-up IP connection - standard X is too fat for this and typically an obscure lightweight X needs to be substituted instead... which Hardly Hever Happens.

It also remembers state information - so you can resume a session where you left off, and the bundle can wrapped up in a browser webtop of your choice. This neatly, and precisely, removes MetaFrame from the equation. Perhaps remembering the fate of Quarterdeck's DesqView/X, SCO is either too canny or too modest to describe this as a platform, which it clearly is, or could be, given some McNealy style marketing. But SCO has a long history of letting its partners take the credit for its work, and is probably wise to risk hubris and position Tarantella as a quick-and-dirty portal, or super-emulator for now. So where does this leave Citrix? While Citrix engineers continue to work on the NT/W2K kernel, the company's most-favoured-nation status quietly expired last month leaving Microsoft to discreetly promote RDP.

Now we know Microsoft has never really rid itself of the idea that owning protocols is a worthy goal. Those little (c) notices on all its BizTalk XML schemas tell us old habits die hard. But Microsoft also knows that right now, with thin client Windows one of the hottest tickets in town, its RDP protocol goes almost completely unused. What it needs is a few half-hearted cross platform gestures - such as punting ActiveX in the direction of the OpenGroup - to give the world the impression that some folk outside the Redmond campus think it's doing The Right Thing.

While it would almost certainly upset Citrix to start licensing and promoting RDP right now, if Microsoft were to look the other way, and whistle, while RDP was cloned - then Microsoft would be in a much stronger position in 2002 when the joint development agreement with Citrix expires. The trouble for SCO is getting anyone to believe they can get away with it, or that if they can, that they can keep it up.

Although the Unix world has reverse engineered Microsoft's file and print protocol SMB for some years, resulting in Samba, it hasn't been easy given that Microsoft has moved the goalposts more than a dozen times. However SCO execs don't think the parallels are exact. A Linux box running Samba is a direct hit on NT server revenues, they reckon, whereas a Tarantella box isn't. SCO isn't looking for a formal license agreement for RDP, but perhaps, a nod and a wink. (Register advice - count your fingers].

Meanwhile the rest of us can savour the irony of a company founded by the OS/2 kernel design team, and which perhaps has done more to legitimise Windows NT in grown-up computing environments, dashing after the Unix market- while the Unix-on-Intel champion, which has dodged fifteen years of mud from Microsoft, rushes to be the very best NT citizen. ®